Offset rotary filing tool



March 13, 1956 .1. o. CINOCCA 2,737,704

OFFSET ROTARY FILING TOOL Filed Aug. 27. 1954 iwsz aiir 66 United States Patent OFFSET ROTARY FILING TOOL Joseph 0. Cinocca, Tulsa, Okla. Application August 27, 1954, Serial N 0. 452,483 3 Claims. (Cl. 29-80) This invention relates to improvements in the construction of abrading tools, such as files, and has for its primary object to provide a self-leveling file which regardless of its initial angle of attack to a work piece will rotate to assume a position level to and in face to face contact with the work piece.

Another object of this invention is to provide a file which includes a handle that rotatably carries an axially aligned head which is rotatable relative thereto and to provide means for attaching a file to the head so that it extends axially therefrom and has its longitudinal center line laterally offset from and paralleling the longitudinal center line of the handle and the head.

A further object of this invention is to provide a compact and inexpensive filing tool which has a self-leveling action as it is pressed down against a working surface.

The foregoing and ancillary objects are attained by this invention, the best known form of which is set forth in the following description and illustrated in the accompanying drawing, wherein;

Figure 1 is a view in perspective of the tool;

Figure 2 is a front end elevational view thereof;

Figure 3 is a longitudinal vertical sectional view thereof;

Figure 4 is an enlarged fragmentary longitudinal vertical sectional view of the head end of the tool;

Figure 5 is a front end elevational view of the tool showing in dotted and full lines the self-leveling action of the file, and,

Figure 6 is a cross-sectional view taken on line 66 of Figure 4.

Referring now more particularly to the drawing, the numeral 10 designates a handle which has a non-circular grip end 12 and a rounded forward end 14. The handle is formed with a through and through axial bore 16 that tightly receives a cylindrical sleeve or liner 18. The rearward end of the handle is counter-bored to provide an internal shoulder 20 and the elongated cylindrical shank 22 of a head 24 is rotatably disposed in the liner 18. The rearward or free end of the shank is formed with a threaded bore 26 which receives the shank of a locking screw 28, which has a thrust bearing 30 on its shank and the thrust bearing is held against the end of the liner in the counter-bored section of the handle by the head of the screw to hold the shank against outward axial movement.

The liner 18 extends axially beyond the forward end of the handle and the extending portion 32 thereof is flared or belled outwardly and forms a rearwardly facing shoulder 34 at its rearward end. The shoulder 34 engages the end terminal of the forward end portion 14 of the handle.

The portion 32 has a coaxially reduced, externally threaded front end 36 which receives a locking nut 38. The end 36 forms a forwardly facing shoulder 40 and the locking nut is rotatable on the end 36 to be moved from the shoulder into wedging engagement of the rear end of the head 24 so as to lock the head against rotation.

2,737,704 Patented Mar. 13, 1956 ice The head 24 is formed with a centrally disposed axial bore 42 which has a counter-bored outer portion 44, the outermost section of which is provided with threads 46. The head is also formed with circumferentially spaced, axially extending bores 48, which are spaced radially from the bore 42 and are parallel thereto. The bores 48 are of diiferent cross-sectional shapes and are provided to receive the tine 50 of a flat file 52. The' various shapes of the bores 48 complement the various cross-sectional shapes of the tines of files. The tine 50 is axially inserted in one of the bores and locates the file in a plane parallel to and laterally offset from the longitudinal center line of the head and the handle.

The head is formed with radially disposed holes 54 which are equidistantly spaced circumferentially of the head and which have inner closed ends 56 which extend radially past the inner plain end of the counter-bored portion 44. Locking balls 58 are housed in the ends 56 of the holes and a common locking member is provided. Such member includes an elongated screw 60 which has a cylindrical inner end 62, an outwardly flared neck 64 and a threaded end 66. The threaded end 66 is engaged with the threads 46 and the end 62 is disposed in the bore 42, while the conical neck 64 exerts a wedging force on the balls, as the end 66 is threaded into the head, and commonly forces'the balls radially outwardly to engage the tines. The inner ends 56 of the holes, of course, communicate radially with the bores 48. The end 62 retains the balls in the ends 56 of the holes when the screw 60 is retracted to release the locking pressure of the balls. If desired, the outer ends of the holes can be plugged up to improve the appearance of the tool.

Also, instead of using the balls and wedging force, the holes 54 may be internally threaded and a single set screw may be provided to selectively lock a tine in one of the bores 48.

In use, a file, locked in one of the bores 48 and extending axially forward of the head and having its longitudinal center line offset radially from and paralleling the aligned longitudinal center lines of the head and handle, is tree to rotate relative to the handle. The handle is, of course, held in the hand and the file will rotate relative to the held handle.

Assuming, as shown in Fig. 5, that the file has been placed on the working surface 68 so that one of its side edges contacts the surface and the file is at an angle to the surface, it can be understood that, upon the exertion of downward pressure on the handle, that is, perpendicular to the surface 68, the file will rotate to a fiat position in face to face contact with the surface 68. The edge of the file forms a fulcrum point on which the file turns as the file and head rotate to bring the file down level on the surface. Thus, no matter how the file is initially addressed to the working surface, it will automatically seek its level and assume a face to face contact with the surface under the downward natural force imposed on the handle in the commencement of the filing operation.

If it is not desired that such action be realized, then the lock nut 38 can be rotated to a position bearing tightly against the end of the head and locking the head to the liner and thereby holding'it against rotation.

While the preferred form of this invention has been described herein and shown in the drawing, other forms may be realized as come within the scope of the appended claims.

What is claimed is:

1. A filing or abrading tool comprising an elongated handle having a centrally disposed axial bore, a head disposed at one end of the handle in axial alignment theremeans locating the shank and the head against axial movement relative to the handle, said head having an axial opening disposed parallel to and spaced radially outward from the aligned longitudinal center lines of the handle and the head, and means fixedly mounting a file in such opening so that it extends axially forward of the head whereby the head and file can rotate to level the file on a working surface, said last means including a radially movable ball and means located along the longitudinal center line and movable axially of the head for moving the ball outwardly into wedging contact with the portion of a file inserted in the opening.

2. A filing or abrading tool comprising a relatively 1'0- tatable handle and head, said head having an outer free end and having an axial bore disposed at its longitudinal center line and opening through the outer end, said head having at least one axially disposed opening spaced radially outward from the center bore and extending through the outer end to receive an end of a file or the like, a

longitudinally movable member adjustably fitted in the bore, said head having a radial groove extending between the bore and the opening, a ball element in said groove and means on the movable member for moving the ball element outwardly in the groove and into Wedging contact with the file.

3. A filing tool as claimed in claim 2, wherein said member is screw threaded in the bore and said means thereon includes a tapered portion for cam engagement with the ball element.

References Cited in the file of this patent UNITED STATES PATENTS 703,869 Weder July 1, 1902 742,640 Harold Oct. 27, 1903 835,160 Sutz Nov. 6, 1906 

